Prior art flat top conveyor chains comprise a plurality of flat top links which are chained together by means of connection pins. In one form of conveyor, each of the flat top links are made from a polyacetal resin. In some prior art embodiments, a fluororesin is employed in an amount ranging from about 2 to 5% by weight.
In the prior system described above, where the fluororesin has been added, that addition is intended to reduce the sliding friction coefficient of the polyacetal resin to thereby improve the sliding characteristics of the articles on the flat top links. This facilitates the use of the conveyor to accumulate the articles on the flat top links, as well as branching and joining of various conveyors for sorting with a minimum of difficulty. One drawback with this system is that fluororesins have a negative effect upon the acetal resins by decreasing the strength of the resin, and therefore the chain, with an increase in the amount of fluororesin admixed with the polyacetal resin. Accordingly, the amount of fluororesin added to polyacetal resin is limited to about 2% to about 5% by weight, as mentioned above. This amount does not adversely effect the strength of the flat top link but also fails to sufficiently lower the sliding friction coefficient sufficiently to obtain desired benefits from the use of the resin.
Accordingly, it is object of the present invention to provide a flat top conveyor chain link which has satisfactory strength and which has a substantially lower coefficient of sliding friction than prior art devices.
Another object of the present invention is to provide a modification of prior art devices which is simple and easy to accomplish.
Other objects will appear hereinafter.